package Filter;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

/**
* @author Jesun
* @date 2008-2-16
* 源码来自Internet,我只作了简单的修改
* 解决Struts中文显示乱码问题
* */

public class SetCharacterEncodingFilter implements Filter {
protected String encoding = null; 
protected FilterConfig filterConfig = null; 
protected boolean ignore = true; //在web.xml文件里定义filter时要用到此参数

public void destroy() {
   // TODO Auto-generated method stub
         this.encoding = null;
           this.filterConfig = null;
}

public void doFilter(ServletRequest request, ServletResponse response,
    FilterChain chain) throws IOException, ServletException {
   // TODO Auto-generated method stub
     // Conditionally select and set the character encoding to be used
        if (ignore || (request.getCharacterEncoding() == null)) {
            String encoding = selectEncoding(request);

            if (encoding != null)
                request.setCharacterEncoding(encoding);
        }
        //Pass control on to the next filter
        chain.doFilter(request, response);

}

public void init(FilterConfig filterConfig) throws ServletException {
   // TODO Auto-generated method stub
   this.filterConfig = filterConfig;
        this.encoding = filterConfig.getInitParameter("encoding");
        String value = filterConfig.getInitParameter("ignore");
        if (value == null)
            this.ignore = true;
        else if (value.equalsIgnoreCase("true"))
            this.ignore = true;
        else if (value.equalsIgnoreCase("yes"))
            this.ignore = true;
        else
            this.ignore = false;
}

    protected String selectEncoding(ServletRequest request) {
        return (this.encoding);
    }

}